EXTRA HIGH ACCURACYHV VOLTAGE DIVIDERS

FOR EXTRA HIGH ACCURACY AND STABILITY: 0.01% DC accuracy types are more limited in resonance free bandwidth than 0.1% types, generally being DC to 1MHz instead of the DC to 5MHz or more for most 0.1% DC accuracy units. 0.1% DC units have in the order of 20-25PPM per degree C temperature coefficient and less than 0.1PPM/volt voltage coefficients. Extra high accuracy types have much lower DC temperature and voltage coefficients, being in the order of 1 to 5 PPM/°C temperature coefficient (0.0001% to 0.0005% per degree C). 0.01% DC and 0.5% to 3% AC units maybe used without full shielding if proximity rules are observed, but for higher AC accuracy full shielding maybe used to obtain accuracies better than 0.5%. Calibration correction charts are provided for all dividers and probes, increasing the accuracy even more if the correction factors are applied to readings.

ACCURACY CONSIDERATION: For highest accuracy in high impedance low input capacitance types, consideration must be given to induced voltage pick-up in leads, corona, effective capacitance, and voltage gradient and capacitance shift related to proximity to ground planes, walls, enclosures, and equipment. Load resistance, and contact potential in cable connectors and switches must also be considered for DC. Both load resistance and capacitance in cables and loads must be considered for AC. The divider should be calibrated with the specific instrument to be used or at least the accurately simulated load, and also with accurately simulated proximity to ground planes, walls and nearby equipment if extreme AC accuracy is required for unshielded or partially shielded dividers. Fully shielded dividers for AC are available but are much larger and heavier. Absolute maximum accuracy is usually centered around 2/3 to 3/4 of maximum DC or PK AC voltage rating unless otherwise required. Certified calibration charts are supplied for approximately 10% to 20% steps from 10% to 100% rated PK operating voltage.